Google has today announced the launch of Ancient Rome 3D, a layer for Google Earth allowing users to explore the ancient city of Rome as it stood in 320 AD, under Emperor Constantine.

Ancient Rome is the first ancient city to be depicted on Google Earth, which was recently released for the iPhone, in addition to the existing Windows, Mac and Linux versions.

Through the layer, users will be able to view over 6,700 of the city's historic buildings in 3D, zoom in close enough to see detailed interiors of 11 buildings, such as the Colosseum, and read about the history of Rome through information bubbles written by historians.

Google are also sponsoring a curriculum contest for K-12 educators in the United States, giving teachers of any grade or subject the chance to win a prize pack which includes an Apple Macbook, digital classroom projector, digital camera and more.

The Mayor of Rome, Gianni Alemanno, said in a post on Google's blog, "What fascinates me most about this project is the accuracy of the details of the three-dimensional models. It's such a great experience to be able to admire the monuments, streets and buildings of Ancient Rome with a virtual camera that lets you go inside and see all the architectural details".

The project was developed in collaboration with Past Perfect Productions, the University of California and the Institute for Advanced Technology in the Humanities at the University of Virginia.

If you want to travel back in time to Ancient Rome, you will be able find Ancient Rome 3D under "Gallery" in the "Layers" panel of Google Earth.